Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 380,005	$ 580,658
Marketable securities	403,140	241,117
Accounts receivable, net of allowance for doubtful accounts of $189 and $105 as of June 30, 2022 and December 31, 2021, respectively	57,418	34,396
Deferred costs, net	22,496	19,666
Prepaid expenses and other current assets	20,494	16,494
Total current assets	883,553	892,331
Property, equipment and software, net	27,862	24,725
Operating lease right-of-use assets	11,510	16,321
Intangible assets, net	9,165	10,091
Restricted cash	2,061	2,061
Other assets	18,239	13,381
Total assets	952,390	958,910
Current liabilities:
Educator partners payable	55,323	49,206
Other accounts payable and accrued expenses	20,876	23,257
Accrued compensation and benefits	16,519	18,353
Operating lease liabilities, current	8,043	8,031
Deferred revenue, current	115,581	94,637
Other current liabilities	7,968	7,639
Total current liabilities	224,310	201,123
Operating lease liabilities, non-current	8,715	11,864
Deferred revenue, non-current	2,665	3,851
Other liabilities	913	559
Total liabilities	236,603	217,397
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.00001 par value- 10,000,000 shares authorized as of June 30, 2022 and December 31, 2021, respectively; no shares issued and outstanding as of June 30, 2022 and December 31, 2021	0	0
Common stock, $0.00001 par value 300,000,000 shares authorized as of June 30, 2022 and December 31, 2021; 148,332,771 shares issued and 145,584,833 shares outstanding as of June 30, 2022, and 144,653,979 shares issued and 141,906,041 shares outstanding as of December 31, 2021	1	1
Additional paid-in capital	1,299,173	1,235,231
Treasury stock- at cost, 2,747,938 shares as of June 30, 2022 and December 31, 2021	(4,701)	(4,701)
Accumulated other comprehensive loss	(2,318)	(252)
Accumulated deficit	(576,368)	(488,766)
Total stockholders' equity	715,787	741,513
Total liabilities and stockholders' equity	$ 952,390	$ 958,910